Precision testing tools installed by general factories, such as tool setting probes, are used for measuring in the state of non-processing and incapable of maintaining the accuracy in the state of processing and for a long time. In order to achieve stabilization in a long time of processing, it is necessary to establish a compensation system to suppress the thermal deformation.
In addition, regarding a controller of a machine tool, it is necessary to purchase extra control cards and input/output cards, increase the memory and modify the interface in order to add a thermal compensation function. After the hardware is completed, it is still necessary to implement modeling technologies after the machine sheet metal interface is removed. Finally, an ideal reference temperature position and a compensation equation are obtained via analysis. In general, the modeling process takes more than one week, and the thermal compensation model can not be easily changed. The original thermal compensation model for the original machine needs to be modified after essential elements (e.g. spindle, oil cooler, etc) of the machine are replaced. If the effect of the replacement is significant, then it is unavoidable to reconstruct the model.
Since the process of thermal compensation is complicated and is an open-loop control system, various factors, such as worn-out of a machine tool and lose of the accuracy of parts, lead to inaccuracy of thermal compensation models. This problem is not overcome immediately until the measurement result of work pieces is obtained so the problem of the compensation distortion is informed. The result will lead to processing errors or machining errors and accordingly it results in losses of time and money.